1. Field of the Invention
The present invention relates to a disc player, which clamps a disc by rotating a chassis on which a clamper or a turn table is mounted.
2. Description of the Related Art
There is a disc player, which pinches and holds a disc between a clamper and a turn table mounted on a rotatable chassis. The chassis is provided with a central shaft which is parallel to a main surface of the disc. This rotation shaft is held rotatably by a bearing provided on a tray or the like. By rotating the chassis with respect to the tray around the rotation shaft as a center by means of an elastic member, a cam etc., so as to swing the turn table, the disc is pinched and held between the turn table and the clamper which is located above the turn table.
On the other side of the chassis, a guide member is formed. The guide member is engaged with a guide rail extending in a direction perpendicular to the main surface of the disc, so as to guide the rotational movement of the chassis. By virtue of the guide member, it is possible to improve the positional accuracy of the chassis and the turn table in the direction of the main surface of the disc. Thus, it is possible to prevent a miss-clamp when claming the disc.
However, in case of the above-mentioned disc player, the position of the chassis in the direction of the main surface of the disc is restricted by the rotation shaft, while the position of the chassis in the direction of the main surface of the disc is further restricted by the guide member. Namely, the movement of the chassis is restricted redundantly by the rotation shaft and the guide member. Thus, by a subtle deformation of the constitutional element such as the chassis or the guide member, a stiffness is generated between the rotation shaft and the bearing or between the guide rail and the guide member, resulting in that the rotational movement of the chassis cannot be smoothly performed.
It is therefore an object of the present invention to provide a disc player, in which a stiffness is not generated in the rotational movement of the chassis on which the turn table or the clamper is mounted, and which can smoothly rotate the chassis, when clamping the disc.
The above object of the present invention can be achieved by a disc player provided with: a turn table (13) for rotating an information record disc, which is placed on the turn table; a clamper (15) for holding the information record disc between the clamper and the turn table; a chassis (10) on which at least one of the clamper and the turn table is mounted and which has a rotation shaft (11a, 11b) parallel to a main surface of the information record disc held between the clamper and the turn table; a driving device (8a, 12) for transmitting a driving force to the chassis so as to rotate the chassis with the rotation shaft at a rotation axis; and an optical pickup (20) for at least reading a signal from the information record disc held between the clamper and the turn table while the disc is rotated on the turn table, wherein a gap (W) is prepared between the rotation shaft and a bearing (22b) for the rotation shaft in a direction parallel to the main surface such that the rotation shaft has a play in the direction parallel to the main surface.
According to the disc player of the present invention, since the rotation shaft has a play i.e., a margin in which the rotation shaft can move, in the direction parallel to the main surface, the rotation shaft escapes in the direction parallel to the main surface within this margin, so as to absorb the stiffness in the rotation movement when the chassis is rotation-driven. Therefore, even if the position of the chassis on the main surface is restricted at a position other than the rotation shaft, it is possible to smoothly rotate the chassis.
In one aspect of the disc player of the present invention, the rotation shaft (11a, 11b) is disposed on one end of the chassis (10), and the disc player is further provided with a guide member (30), which is disposed on the other end of the chassis, for guiding a rotation movement of the chassis around the rotation shaft.
According to this aspect, since the guide member for guiding the rotation movement is provided on the other end of the chassis, it is possible to prevent a miss clamp of the disc at the clamper and the turn table since the positional accuracy of the chassis in the direction parallel to the main surface can be certainly improved. Further, since the rotation shaft has a play in the direction parallel to the main surface, the rotation shaft escapes in the direction parallel to the main surface, so as to absorb the stiffness in the rotation movement when the chassis is rotation-driven. Therefore, even if the rotation movement of the chassis is redundantly restricted by the rotation shaft and the guide member, it is still possible to smoothly rotate the chassis.
In another aspect of the disc player of the present invention, the rotation shaft (11a, 11b) is disposed on each side of the chassis (10), and the gap (W) is prepared on only one side of the chassis.
According to this aspect, since the gap is prepared on one side of the chassis between one rotation shaft (11b) and one bearing (22b) while the gap is not prepared on another side of the chassis between another rotation shaft (11a) and another bearing (22a), the rotation movement of the chassis can be smoothly and stably performed.
In another aspect of the disc player of the present invention, the rotation shaft (11b) is formed by shaving off both sides of a rounded shaft member so that the gap (W) is prepared in correspondence with shaved off portions of the rotation shaft member as the rotation shaft.
According to this aspect, it is relatively easy to prepare the gap between the rotation shaft and the bearing.
Alternatively, in another aspect of the disc player of the present invention, the bearing (41) has an inner size wider than a diameter of the rotation shaft (40) so that the gap is prepared in correspondence with a difference between the inner size and the diameter.
In another aspect of the disc player of the present invention, the disc player is further provided with a loading tray (1) for loading the information record disc, and the bearing (22a, 22b) is formed on the loading tray.
According to this aspect, the information record disc can be certainly loaded to the disc player by the action of the loading tray.
In this aspect, the disc player may be further provided with a rotational tray (3), which is rotatably disposed on the loading tray (1) and which has a plurality of disc accommodation rooms (3b) each accommodating one information record medium.
In another aspect of the disc player of the present invention, the optical pickup (20) is mounted on the chassis (10) movably in a radial direction of the information record disc held between the clamper (15) and the turn table(13).
According to this aspect, the reproduction operation and/or recording operation can be accurately performed while the optical pickup is moved on the chassis, which is smoothly rotated.
The nature, utility, and further features of this invention will be more clearly apparent from the following detailed description with respect to preferred embodiments of the invention when read in conjunction with the accompanying drawings briefly described below.